Fighting immunisation preventable disease in primary care

In New Zealand, the immunisation programme has eliminated polio and controlled tetanus and diptheria. However, disease persists, as seen with high rates of pertussis and recurrent epidemics of measles. With better coverage and improved timeliness of immunisation, the gains could be higher.

Coverage and timeliness maximise success of immunisation

Childhood immunisation is one of the most cost-effective activities in health care. In New Zealand, the immunisation
programme has eliminated polio and controlled tetanus and diphtheria. However, disease persists, as seen with high rates
of pertussis and recurrent epidemics of measles. The burden of disease disproportionately affects Māori and Pacific
children. With better coverage and improved timeliness of immunisation, the gains could be higher.

Immunisation Coverage

While much of New Zealand historical coverage data has not been accurate, there are three coverage surveys using robust
methodology involving random sampling of geographical clusters to ascertain children's immunisation status.

Coverage Survey Results

Timeliness of Immunisation

Achieving good disease control requires not just high coverage, but immunisation events to be delivered on time. Delay
in receiving the first immunisation in the primary series is one of the strongest predictors of subsequent incomplete
immunisation.4 Also a delay in timeliness affects disease control. A child with delayed
immunisation in the primary course has a 4.5 times increased risk of being admitted to hospital with pertussis.5

Overcoming barriers to immunisation coverage and timeliness

The major factors leading to incomplete immunisation are socioeconomic factors (poverty), provider and system factors,
and parental/community attitudinal factors.

Provider commitment is the key

The commitment of the provider is the most important determinant of immunisation coverage. Effective, motivated primary
care can achieve good immunisation uptake, even in the face of socioeconomic deprivation and parental low confidence.
Despite mediocre national coverage, some primary care providers with strong commitment to immunisation delivery can, and
do, achieve high coverage rates.

Provider knowledge overcomes false immunisation beliefs

Health provider knowledge is a significant factor in obtaining high immunisation coverage. While GP attitudes to immunisation
in New Zealand are positive, our knowledge base is not as strong. A national survey reviewing GP knowledge revealed significant
knowledge gaps around false contraindications.6

Genuine contraindications to immunisation

Children with minor illness (without an acute systemic illness and with a current temperature below 38.5°C) may be vaccinated
safely.

Major illness or high fever may be confused with vaccine side effects and increase the discomfort for a child. In this
case the vaccination should be postponed 2-3 days until the child is well. It is a good idea to make a return appointment
at the time of deferral.

A practice visit is an opportunity for immunisation

A visit to primary care when a child is due a vaccination but does not receive it, is a missed opportunity. This is
one of the most important factors contributing to decreased immunisation coverage and timeliness. Missed opportunities
are happening almost universally in New Zealand primary care. Recent research7 has shown
that on auditing a subgroup of children in 62 practices, 97% of practices had missed opportunities to vaccinate. Of the
records audited, 30% of the children had had a missed opportunity, with the most common reason being a visit for an URTI.
Genuine contraindications were shown in less than 5% of cases. Surprisingly 10% of the missed opportunities occurred at
well child visits.

Guide to the contraindications for vaccination

Vaccine

Contraindications

All

Fever greater than 38.0°C

Moderate to severe acute illness without fever >38.0°C

Anaphylaxis, allergy, or anaphylaxis reaction to any vaccine component or previous
dose

Other than simultaneously administered vaccines (at different injection sites),
the patient having had a previous live virus vaccine within the last 4 weeks

The patient having received blood or human immunoglobin within the last 6 months,
or is about to in the next 3 weeks

Immune suppressed patient

Influenza, yellow fever

Anaphylaxis to eggs or chicken

Some conditions increase the risk of complications from infectious diseases
and children and adults with such conditions should be vaccinated as a matter of priority

These conditions include:

Asthma

Chronic lung and congenital heart conditions

Downs Syndrome

HIV infection

‘Small for date babies’ and premature babies

Practice systems impact on immunisation rates

A range of practice policies and systems have considerable impact on immunisation uptake. Vital systems for high immunisation
rates include:

A clear enrolment policy

Early enrolment of children

Good data entry of records

Systematic precall* & recall

Regular audit

*Precall is a reminder sent prior to the vaccination being due

While around 60-70% of children receive immunisation with a simple precall system and organised practice, the other
20-30% requires extra time and effort in tracking and recalling. This requires committed staff time, a good understanding
of how to use a PMS and effective use of National Immunisation Register (NIR) status queries. Practices with high staff
turnover or inexperienced staff are likely to have greater problems with entering quality, accurate data.

There are significant numbers of errors occurring in immunisation data entry at the practice level. Recommendations
to improve this include early enrolment of infants, standardised approaches to entering data, checking data entry quality,
improving staff training in use of the PMS, and developing a focus on timeliness, as well as coverage, with regular audits.
Performance feedback to the practice has been shown internationally and locally to improve coverage rates.

Other important ways to improve immunisation coverage and timeliness include making immunisation services available
at all possible hours, and having staff available at all times who can vaccinate (including GPs if the practice nurse
is not present).

Parent/Community knowledge and attitudes

In New Zealand it is known that 20% of parents consider that good healthy living will be enough to prevent disease without
the need for vaccination.8 Caregiver's knowledge and attitudes impact on immunisation uptake
to a lesser extent than practice characteristics but the impact is still significant. The media, fuelled at times by the
anti-immunisation lobby, can have dramatic effects on parental confidence in vaccination as has been seen with the abiding
myth that MMR may be linked to autism despite the lack of any scientific backing.

The importance of the primary care provider relationship with the parent is vital to parental confidence. A knowledgeable,
committed and confident provider with a good relationship with their patients, is likely to overcome many parental myths
and concerns.9

Practice Strategies that Promote High Coverage/Timeliness

Improving immunisation coverage and timeliness of delivery is a practice-level issue. The answers lie in good practice
systems, dedicated staff time and regular commitment of all clinical staff to regularly review progress.

**The Immunisation Advisory Centre, University of Auckland,
is launching a web-based online update course in April 2007. Visit
www.icomet.org.nz

Key factors are:

Enthusiastic and committed staff

Enrolling children as early as possible

Accurate immunisation data entry in the PMS

Using NIR status queries to update records

Timely precall system

Attractive, engaging precall and recall letters

Early and systematic recall follow up, first recall within 2 weeks of the due date